questions re batteries

[AlanH]

Alan:
I'm mid way into replacing solar array on my boat, using 5-43 watt Kyocera panels. ($235 USD each from an outfit in Renton Wa.) They come well recommended as a quality PV module - take care, all solar panels are NOT created equal!!!

Jim/Haulback

I'm thinking that I can get two 43 watt panels, and hook up one, each, directly to each battery through a basic charge regulator. Looks like the panel puts out 17 volts, so I guess I'll need the regulator. The batteries are standard 12v wet cells, deep cycle. It looks like the panels put out 2.2 amps at peak, so if that happens for 8 hours a day, me thinking that it's July, but then peak power-producing time is still only from about 10:00 AM to 6:00 PM that means I get something like 15-17 amps back in my batteries each day. 'zat make sense?

I'll be using the Navik along the coast, so it'll just be the radio and the LED's that suck down power for the first few days. I think they will mostly keep up with the drain. I might need to run the Lightning generator (has a 15 amp alternator) for a couple of hours, maybe twice in the middle of the trip, but that's OK.

Who's the outfit in Renton?

[AlanH]

Does anyone have experience using small gas-driven generators. I'm wondering if I could run one a couple of hours each day to charge my battery system. Also could I use it while I was transmitting or would it cause interference?

I have a no-longer-made Lightning generator. It's noisy as hell, but it does put out the juice, as it's specifically made for charging batteries. The stinker with most of the generators out there now is that they're made to supply 110 current, not charge batteries. So they put out 110, and a steady 110, but the amperage at 12 volts that they dish up is kind of wimpy. I've never tried linking up a portable generator to a 10 amp battery charger, but I understand that you lose a lot of efficiency. However, it CAN be done, and it WILL work.

The new generators are a hell of a lot quieter than my Lightning, that's for sure.

[davidmgarman]

Alan, here is what we did on Giant Slayer (sc27) for two pacific cups and we are signed up to go next summer too.

3 85 amp hours gell batteries. two battery banks. We had two main batteries and one backup. We had the SSB wired to the backup. We had a traditional cross over OFF, 1,2, Both battery switch for the two banks. We had a voltage regulator from Ample Power. We also could from a small switch panel charge bank 1 or 2 or both. The regulator is isolated for two banks so you wont backflow from bank to bank. You can also go open mode (no regulation at all) with either or both batteries. We had the power/voltage/amp meter and used the shunt as the boats common ground point. We know better than to share grounds and run all ground wires to a common large terminal strip. That way everything has the same ground and ground loops in instruments and radios etc etc are minimized. We had a singe BP marine solar panel. The autopilot can feed off this circuit or from the panel too, saves a little power and some wire, but with some risk. We use 10 guage wire. for power. We would top off the SSB battery some time in the day if we had extra power, but that can run your SSB all the way to HA if you just keep to business of position and turn it off. Also, you can run the house bank down to 35% if you have to and still run your instruments and autopilot. If you did run the 170 amphr bank to 35%, then it will take you 2 days to get it back to 95% charge. Storms happen. I like the single panel on the transom and tilt it to get full charge. A backup panel might be a good idea too, but we did not want more stuff on the boat. The little bit of extra voltage you get from turning off the regulator is worth the risk (i believe) to get the extra 5% of charge. Also Gels go full charge at a lower (and more powerfull) voltage limit. With the lower internal voltage loss, they work well, cant spill, dont vent (much) and have a long life.
We made a small strong shelf under the chart table of the SC27 standard cabin for one battery. This was the SSB battery mentioned above. Short wire leads to the radio mounted to the underside of the deck above. One battery was mounted below the chart table to the floor of the cubby. One was mounted under the chair in the normal location. This is good weight placement. If you went with two batteries, i would still use two banks. We had a broken wire in the second trip, very hard to figure out why the voltage would jump around when the contact was remade occationally since one battery was not charging but both seemed to be supplying??. but we were able to wire around that piece of wire and figure it out after two days. with the confidence that we had a fresh backup battery just waiting, safely on its own circuit. We dont intend to be lost as sea, so you have to weigh the extra 60 lbs of battery for 14 hours of autopilot if that is more important than the radio. We run our insturments, GPS, and stereo 24/7, and with the 75 watt panel, we usually arrive in hawaii fully charged. GOOD LUCK. Im curious what sail size you use for your twin jib rig and to you fly the windward sail in the grove or free. david

[haulback]

Alan
Panels were from ABS Alaskan in Renton, Washigton State - phone number 425 251 5745.

They just got a shipment of that size panel in a few weeks ago, so may still have some left, otherwise expect to maybe wait for a while....but there ain't no sunshine now 'til sometime towards the end of february, (at least up this way) so what does it matter anyhow??

Jim

[seabird51]

Can anyone help? If one has a 24 V boat how do you deal with 12 v solar panels? Lets assume I purchase 2 SunlinQ portable panels each rated 12V/25 Watts (nominal V= 16.5 v, nominal A= 1.5)
Can I hook them up in series to get 33 v. Then how many amps do I get ?
Do I reallly need 4 to get a signif current?
Thanks
Lou

[dogbark]

Lou, same as batteries. When connected in series double the volts, but same amperage. You need to decide whether that is enough, but I would guess Seabird would need a lot of panels to be solar self sufficient. Al

[seabird51]

So if I got 4 panels and put each pair in series and hooked the pairs up in parallel I would get 3 A and with 10 hr of perfect sunlight I could put 30 A into bank. Pretty austere for Seabird. That's about 30 min of gen time. Maybe I should look at larger panels or take very good care of genset.
Happy New Year Al
Lou

[dogbark]

Yep, you got it. Or perhaps less ice cream, prime rib or dvds. Oh sorry, I know it's been almost 18 months but there still is a little jealousy here. Have a nice cigar and enjoy the new year, Al